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		| Paper: | 
		Far-infrared properties of high latitude cirrus clouds | 
	 
	
		| Volume: | 
		132, Star Formation with the Infrared Space Observatory (ISO) | 
	 
	
		| Page: | 
		153 | 
	 
	
		| Authors: | 
		Laureijs, R. J.; Haikala, L. K. | 
	 
	
	
		| Abstract: | 
		Far-infrared scans in the 60, 90, 135 and 200 microns filter bands of ISOPHOT were obtained for 4 quiescent high latitude clouds. The targets have been selected from IRAS images and have different central opacities spanning a range from less than one to several magnitudes of visual extinction. For each cloud we find that the ratio between the emission in the C_135 and C_200 bands (I135/I200) is independent of the strength of the C_200 emission. This suggests that the observed dust temperature is constant throughout each cloud. On the other hand we find that I135/I200 varies from cloud to cloud indicating global temperature variations between clouds. The 60 microns emission was marginally detected. At 90 microns we have measured a significant decline in emission towards the centre of the clouds. This indicates that a fraction of the emission in the 90 microns band is due to a dust component different from the one giving rise to the 135 and 200 microns emission. | 
	 
	
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